Improvement in valve-gear for steaivl-engsnes



s. E. WHEELER.

VQALVE-GEAR FOR STEAM-ENGINES.

Patented Feb. 27. 1877.

I nvento r M@ Vgl/;

UNITED' STATEs PATENT EEICEG SAMUEL H. WHEELER, OF SAN FRANCISCO,CALIFORNIA.

IMPROVEMENT IN VALVE-GEAR FOR STEAWl-ENGENES.

Specification forming part of Letters Patent N o. 187,947, datedFebruary 27, 1577 application tiled September 9, 1876.

To all whom it may concern:

Be it known 'that I, SAMUEL HOWARD WHEELER, of the city and county ofSan Francisco, State of California, have invented au ImprovedValve-Motion for Steam and other Engines; and I do hereby declare thefollowing description and accompanying drawings are sufficient to enableany person skilled in the art or science to which it most nearlyappertains to make and use my said invention without further inventionor experiment, reference being had to the accompanying drawing.

The object of my invention is'to give such a distribution oi' steam orother Huid in recip rocating engines as that the motion of the mainpiston of the engine shall correspond both inextent and time of movementwith the motion impressed upon the distribution-valve of the engine, thedistribution-valve being operfred by any means independent of the mainengine, as, for instance, by manual force, or

t by an auxiliary or supplemental engine, This accomplish by placing amovable seat under the distribution-valve and connecting it to the mainpiston in such a manner as that, when the motion ofthedistribution-valve upon this seat gives steam behind the main piston,the motion thus impressed uponv the piston will be communicated to themovable seat and will cause it so to move under the distribution-valveas to cut oli' the steam-supply. By this means the motions of the mainpiston are made to correspond with those of the distribution-valve, thepiston moving while the valve is in motion and coming to rest when thevalve is arrested.

This valve motion, while it has for its object the regulation of themotion of the main piston of the engine to correspond with the motion ofthe piston of a supplemental engine or the hand of an operator, as inthe Letters Patent af the United States issued to me J uly 25, 1876-,and numbered 180,401, and in those issued to H. Davey, September 7,1875, num bored 167,509, has this diiierence from them that in thisinvention .the distribution-valve always makes its full stroke forwardand backward during continuous working of the engine, while by thecombination described in those patents the valve is constrained by themotion of the mainpiston to remain very near to its middle position.

In this invention, on account ot' the combination ot' parts that I usein it, the motion of the main piston corresponds both in extent and timewith the motion impressed upon the main valve. In the accompanyingdrawing is illustrated the application ol' my invention to a pair ofrotative engines designed to be used on a foundry-crane. In thisinstance motion is given to the distribution-valves through the mediumot' a shaft and eccentric operated by a crank-handle. The crank-handlebeing turned by the attendant, the engine-shaft will receive acorresponding,` motion and-will continue its motion, stop or reverse,just as the hand of the attendant may be moved.

This arrangement I consider to be particularly well adapted to this andsimilar purposes, as, for instance, steering-gear for ships, since themotion of the engine is under complete control. In applying my inventionto a single direct-acting pumping-engine I would give motion to thedistribution-valve by means of a cataract-engine, the piston-rod ofwhich could be attached directly to the valve-rod, which would thusreceive a regular and continuous reciprocating motion.

In the accompanying drawing, before referred to, A is the steam-cylinderB, the piston; C, the piston-rod; D` the cross-head; E, an arm attached.to the cross-head and connected by a pin to one end of a link, F, theother end of which is jointed to one end ofthe lever Gr. The lever G hasits fulcrnm at the joint of its connection to the link H, which isattached to the steam-chest. The rod I ofthe movable valve-seat K isjointed to the lever Gr at a suitable point between H and F. The movableseat K has passages T', X', and V' corresponding to the thoroughfares Tand V and the-exhaust Xin the main cylinder. These passages andthoroughfares are "so proportioned to one another that each will alwaysbe in communication with its correspondent and no other. L is thedistribution-valve sliding in the movable seat. The face of the valveand the passages in the movable seat are proportioned to each other inthis case the same as though the seats were fixed, and without eitherinside or outside lap. M is the valverod guided in the guider N, andjointed to the eccentric rod 0, the strap of which embraces theeccentric R, fastened on the shaft S. Means of turning the shaft S isprovided by the crank-handle Y.

The operation is as follows: Supposing that the engine is to be operatedby steam, and that communication has been made with the steam-boiler bythe arrangement of the mechanism, the engine will have placed itself sothat both valves will cover the passages V and T'. Now, if thecrank-handle is turned, motion will be given to both valves, and steamwill be supplied behind the two pistons to cause the main crank-shaft toturn in the same direction as the eccentrlc shaft has been turned. Thismotion of the main pistons will be communi cated through C, D, E, F, G,and I to the movable valve-seats, to cause them to lnove in the samedirection as the distribution-valves L have been moved, thus tending tocut oi the supply of steam that has been given by the valves L. Now, ifthe valves L are stopped in their course, the piston B will continue tomove until the movable seats K have completely cut 01T the steam byclosing the passages T and V. They will then stop and remain stationaryuntil motion is again given to the crank-handle Y, and through itsconnection to the distribution-valves L. if the motion -of thecrank-handle Yh-is made continuous, the motion of the pistn B Will alsobe .I claim as new, and desire to secure by Letters Patent, is-

The combination, in a reciprocating engine,

of a movable valve-seat, K, actuated through a fixed connection ofintermediate mechanism by the main piston B, and a distribution-valve" tL, moved by a means independent of the main@ engine, whereby the time ofthe stroke in either direction is controlled by the operator,substantially as described, and for the purpose set forth.

In witness whereof I have hereunto set my hand and seal.

SAMUEL H. WHEELER.

Witnesses:

OLWYN T. STAGY, FRANK A. BBooKs.

